Surgical procedures often require a surgeon to gain access to a cavity in a patient's body. Generally, when such a procedure is required, an incision is made in an exterior wall of the cavity and an instrument is inserted into the working channel created by the incision. One common instrument used in such a procedure is a trocar assembly. Trocar assemblies include a variety of components, but generally can include a trocar cannula, a trocar obturator, and a trocar housing. In many designs, in order to access the body cavity, the trocar cannula is directed through the skin and the trocar obturator is inserted through an interior lumen defined by the cannula. The trocar obturator is then used to penetrate the skin, which has often already had an incision made in it with a scalpel or similar device, and access the body cavity. More specifically, in some designs, applying pressure against a proximal end of the trocar obturator allows a sharp point at a distal end of the trocar obturator to be forced through the skin until it enters the body cavity. Then, the trocar cannula is inserted through the perforation made by the trocar obturator and the trocar obturator is withdrawn, leaving the inner lumen of the trocar cannula as a path to access the body cavity from outside of the body.
The trocar housing can be joined to a proximal end portion of the trocar cannula, and further, the housing can define a working chamber with an open distal end portion that is in communication with the interior lumen of the cannula. Just as the interior lumen can receive the obturator, it can also receive other elongated surgical instruments such that the instruments can be axially extended into and withdrawn from the cannula through the proximal end portion of the working chamber defined by the trocar housing. For example, in order to allow a surgeon to more easily see during a procedure, an endoscope can be inserted through the cannula and proximal or into the body cavity. Further, it is common for one or more seals to be disposed within the housing and/or the cannula to help prevent fluid or gas from escaping during surgical procedures. Such prevention is needed, especially during certain minimally invasive surgical procedures, in which an insufflations gas is used to expand a body cavity. In many instances, at least two seals are used to help maintain a seal while instruments are passed into and out of the working channel.
Once a procedure is completed, the trocar is removed and the opening (sometimes referred to herein as a wound) that was formed through which the trocar is inserted is typically closed. The size of the opening will depend on the size of the trocar. Some common trocar sizes include trocars identified as 5 millimeter trocars, 8 millimeter trocars, 12 millimeter trocars, and 15 millimeter trocars, with the size correlating approximately to the inner diameter of the cannula. At least for openings that are 8 millimeters wide or larger, suture is typically used to close the opening to prevent herinations after surgery. The stitching of the opening is typically done after the trocar is removed, or at least a housing portion of the trocar, and thus the ability to insufflate at that point is lost. The stitching up process typically involves using additional tools and performing several extra steps after the primary surgical method has already been completed. This leads to increased difficulty in closing the opening, an increased amount of time to perform the surgery, and a greater likelihood for unnecessary trauma to the tissue surrounding the opening. It can be particularly tough to stitch the opening when the cavity wall in which the opening is formed is thick, e.g., approximately equal to or greater than three-quarters of an inch, as is often the case for abdominal walls.
Accordingly, there is a need to reduce or eliminate the need for extra tools to be used to close an opening through which a trocar is passed during a surgical procedure, and to reduce the amount of steps required to close the opening. The solution should provide for a more convenient and easier way for surgeons to close the opening and reduce possible trauma to the surround tissue and the patient generally.